Rheostat



(No Model.)

R. W. NEY.

RHEOSTAT.

No. 603,027. Pat ented Apr. 26, 1898.

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ROSCOE WV. NEY, OF NEW ROCHELLE, NE\V YORK, ASSIGNOR TO THE ZUCKER & LEVETT & LOEB COMPANY, OF NE\V YORK.

RH EOSTAT.

SPECIFICATION forming part of Letters Patent No. 603,027, dated April 26, 1898.

Application filed February 5, 1897. Serial No. 622,122. (No model.)

To aZZ whom it may concern:

Be it known that I, ROSCOE NV. NEY, a citizen of the United States, residing at New Rochelle, in the county of \Vestchester and State of New York, have invented certain new and useful improvements in rheostats for regulating the current used in electroplating and other processes, of which the following is a full, clear, and exact description, which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form part of the specification.

The primary object of this invention is to provide a convenient, cheap, and effective regulator applicable to regulating or control ling the amount of current flowing through a plating-tank, it being desirable to keep a constant potential at the terminals of said tank and provide means to increase the current in proportion to the decrease of resistance (or increase of surface of the work in the platingtank) and to decrease the current under (and in direct proportion to) changes in the opposite direction. It is also applicable in other relations to control the strength of the electric current.

The invention consists of a number of resistance strips of different capacities arranged in parallel and connected electrically to a conductor at one end and separated electrically at the opposite end in combination 'with a suitable device by means of which one or more or all of the resistance-strips may be interposed in the circuit.

In the accompanying drawings, which illustrate examples of my invention, Figure l is a plan view, and Fig. 2 is a side view, of one form of device, and Fig. 3 is a plan view, and Fig. 4t is a side view, of another form of device, all including my invention.

It is convenient to make a regulator wholly independent of any other mechanism, and I therefore show my rheostat mounted upon a suitable support or frame A. This may consist of any suitable support, a convenient form being that shown in the drawings, in which the frame consists of end pieces 211 and braces 00 as, the whole being attachable by the feet w w.

B is a suitable metal strip secured to but insulated from the frame A, and to this strip a leading-in conductor a is attached through the binding-post a. To the part B, furthermore, are suitably secured the ends of resistance-strips b, c, d, e, f, g, and h. The opposite ends of these strips are each secured to suitable contact parts 2' t', arranged in an arc and electrically separated from each other.

A leading-out conductor is secured to a suitable binding-post j, electrically connected by means of the strip 7c to the fan-shaped switch m, provided with an insulated handle n and having a contact part Z, corresponding in configuration to the are formed by the parts it and adjusted relatively thereto to bear against such parts t' 2' when the switch m is brought opposite to them. The contact part Z and leading-out conductor j are electrically connected through the pivot 7t or otherwise in any suitable manner. The scope of movement of the switch on maybe limited by suitable detents p q, if desired, on the frame A.

In the example of my invention shown in the drawings the resistance-strip b is twice the electrical resistance and one-half the sectional and superficial area of the other resistance-strips, and any one of the resistancestrips is of such size that it will safely stand the entire potential of the dynamo with which it is to be used withoutinjuriousheating. It, now, work having a certain superficial area be placed in the tank and the switch m placed so that the current will travel only through resistance-strip I) and it be found that a current of fifty amperes is flowing (this being the current desired) and that an electric pressure of two volts be maintained at the terminals of the tank, then to get the proper conditions with treble the superficial area of work in the tank would require one hundred and fifty amperes or three times the current, which will be obtained by moving the switch so as to put strips 1) and 0 into the circuit. The condi tions would then be resistance in rheostat one-third of former resistance and the current will be three times the former current or one hun dred and fifty amperes, the electrical pressure two volts at terminals of tank. Since the electrical pressure at dynamo is assumed to be constant and in practice is nearly so, and as the relative resistance of tank and rheostat under proper working condition is always the same, it follows that a constant pressure will be maintained at terminals of plating-tank. By the use of the conductors in parallel the radiating-surface is increased in proportion to the currents carried, so that when carrying the maximum current the strips are all brought up to the highest safe temperature. Every part of the resistance-strips is therefore working to its fullest capacity.

In Fig. 3 and l- I have shown another example of my invention, in which a sliding switch m is employed. In this example of my invention the contact parts 4; t' are shown disposed in a straight line and the switch m slides between the piece 0' under the strip which is electrically connected through the binding-postj to a suitable leading-out wire, and the pieces .9 s, which keep it in line with the contact ends 1' t'. Projecting parts 1) and q are disposed in the path of the handle a to limit the scope of movement at each side of the sliding switch on.

By the use of several strips of the same sectional and superficial area and resistance in parallel with each other and with one strip of one-half the sectional and superficial area and resistance of the others it is possible to get a greater number of graduat'ions of resistance than the number of resistance-strips employed. Thus if a certain fixed electrical pressure be maintained at the terminals of the rheostat and such pressure is found sufficient to force fifty amperes through the narrow strip Z) it would force one hundred through any one of the other strips. Therefore starting the switch m at the extreme left at the strip 7L and moving the switch toward the right currents would be obtained of one hundred, two hundred, three hundred, four hundred, five hundred, six hundred, and six hundred and fifty amperes, and starting with the switch at the extreme right and moving the switch to the left currents of fifty, one hundred and fifty, two hundred and fifty, three hundred and fifty, four hundred and fifty, five hundred and fifty, and six hundred and fifty amperes would be obtained. It is therefore possible to get thirteen different combinations for seven resistance-strips, and thereby afford a more complete and finelygraduated control of the current.

The switch on, which I have shown as the device for throwing in and out of circuit the resistance, is the most convenient, I believe, for practical purposes; but I do not limit myself to that form of switch, as other switches may also be employed for the purpose, if desired, and the parts i 2' may be placed in one or more straight rows instead of in the arc form without departing from my invention.

By the employment of this my invention there is great saving in metal and framework, and a rheostat is produced which is much lighter, cheaper, and better adapted to nice graduations of current than any which have heretofore been devised, so far as I know.

In the example of my invention shown in Figs. 1 and 2 of the drawings I have figured strips Z) c, &c., and shown the parts broken across to emphasize the fact that the strips need not be extended in a straight line of the length of resistance required, but may be folded upon themselves in any manner desired. Furthermore, the strips may be covered with or inclosed in anysuitable material such as is well known in the art, and while I have shown and described strips I desire to say that I do not limit myself to that form, but that wires may also be employed, if desired, and a greater or smaller number of resistances than shown may be employed, and also more than one fractional resistance 1) may be employed, depending upon the number and character of graduations desired.

Having thus described my invention,what I claim as new, and desire to secure by Letters Patent, is-

In a rheostat, a suitable supporting-frame, end pieces, and two bars which connect the pieces together, a metallic strip secured to the upper end piece, and to which is attached abinding-post; and the resistance-strips,combined with suitable contactparts to which the ends of the resistance-strips are secured, but which contact parts are electrically separated from each other; the binding-post as j, and the connecting-strip as 7; connected to the post, and a switch which has its edge to pass under the ends of the contact parts, substantially as shown.

ROSCOE \V. NEY.

IVitnesses:

CARLTON B. Prnncn, JOHN E. EUsTIs. 

